Synthetic Acid and Associated Methods

ABSTRACT

Glycine is an organic compound that can be used in the making of a synthetic acid that obviates all the drawbacks of strong acids such as hydrochloric acid. The new compound is made by dissolving glycine in water, in a weight ratio of approximately 1:1 to 1:1.5. The solution is mixed until the glycine is essentially fully dissolved in the water. Once dissolution is complete, hydrogen chloride gas is dissolved in the solution to produce the new compound, which can be referred to as hydrogen glycine. Also disclosed is a method for adjusting the pH of a fluid, the method comprising adding an effective amount of a solution to the fluid for adjusting the pH thereof to a desired level, wherein the solution is prepared by mixing glycine in water to form a glycine solution; and adding hydrogen chloride to the glycine solution.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a Continuation of, and claims priority to, U.S.patent application Ser. No. 15/131,364, filed Apr. 18, 2016, whichitself is a Continuation of U.S. patent application Ser. No. 14/739,227,filed Jun. 15, 2015, now U.S. Pat. No. 9,315,400, which is aContinuation of U.S. patent application Ser. No. 14/471,055, filed Aug.28, 2014, now U.S. Pat. No. 9,056,815, which itself is a Divisional ofU.S. patent application Ser. No. 13/110,330, filed May 18, 2011, nowU.S. Pat. No. 8,853,446, which itself claims priority to U.S.Provisional Application Ser. No. 61/417,948, filed Nov. 30, 2010, thedisclosures of which are hereby incorporated by reference in theirentirety and all commonly owned.

FIELD OF THE INVENTION

The present invention relates to compositions comprising synthetic acidsand to methods of use for such compositions, including, but not limitedto, removing cementitious materials from surfaces, hydraulic fracturingof oil and gas wells, adjusting the pH of well drilling fluids,adjusting the pH of process and waste waters, and solubilizing calciumcarbonate in aqueous suspensions or dispersions thereof.

BACKGROUND

Acids by their very nature can be dangerous to use, handle, transport,and store. Further, most acids are not environmentally friendly.

Hydrochloric acid, for example, is a highly corrosive, strong acid thatis used in many industrial and household applications including, but notlimited to, surface cleaning and descaling operations, oil wellacidification and hydraulic fracturing, and in the food industry.Concentrated hydrochloric acid is known to fume, forming an acidic mistthat is corrosive and dangerous to both living tissue and metals.

Therefore, it would be beneficial to provide a synthetic acid that issafe to use for a plurality of applications and does not harm theenvironment or the user.

SUMMARY

The present invention is directed to a synthetic acid, method of making,and method of using. The acid comprises a glycine compound that is madeby mixing glycine with hydrogen chloride gas.

The synthetic acid can be used in place of a plurality of known acids,oxidizers, and disinfectants, such as, but not intended to be limitedto, hydrochloric, hydrofluoric, sulfuric, urea sulfuric, sulfamic,glycolic, acetic, phosphoric, nitric, formic, and citric acids, as wellas urea hydrochloride, sodium hypochlorite, urea phosphate,formaldehyde, and quaternary ammonia.

Particular uses, also not intended as limitations, can include surfacecleaning, concrete etching, hydraulic well fracturing, filter cakebraking/cleaning, cementitious material removal, acidizing of wells,fruit and vegetable peeling, food preparation surface cleaning, turf andsoil treatments, inert to herbicides and pesticides, agriculture andfarm remediation, disinfecting, solubilizing calcium carbonate inaqueous suspensions and dispersions, treating waste water and industrialprocess water, and surface rust removal, and as a neutralizing agent tolow pH acids.

It has further been discovered that this new compound can be consideredorganic, and can thus be deemed “organic” by the USDA. This will be ofgreat benefit to all organic farmers and growers, whose current optionfor a low-pH soil mitigation or a low-pH inert is vinegar (glacialacidic acid), which in most cases is rendered useless for the intendedapplication. Hydrogen glycine, being considered by the USDA as organiccertified, is a viable alternative to the far-less-useful vinegar, asthe pH of raw hydrogen glycine is −0.42, substantially exactly in linewith that of hydrochloric or sulfuric acid.

Another benefit of the new compound is that it causes substantially nofuming during use, which is a great improvement over other known,traditional acids.

DETAILED DESCRIPTION OF EMBODIMENTS

A description of embodiments of the present invention will now bepresented by way of example.

Glycine is an organic food grade compound having the formula NH₂CH₂COOH.Glycine is a crystalline solid that is known to be used commercially inpharmaceutical applications, as an agent in metal complexing andfinishing, as an animal food additive, and in cosmetics.

The current applicant has found a new use for glycine, and that is inthe making of a synthetic acid that obviates substantially all thedrawbacks of strong acids such as hydrochloric acid.

The new compound is made by introducing glycine to water, for example,by way of an eductor jet pump, until the glycine is fully introducedinto the water, in a weight ratio of approximately 1:1 to 1:1.5. Forexample, in a particular embodiment, when using a 10,000-gal batchreactor, 31,800 lbs. of glycine are dissolved into 32,600-48,600 lbs. ofwater. The solution is mixed, for example, with an inline static mixeruntil the glycine is essentially fully dissolved in the water.

Once dissolution is complete, hydrogen chloride gas is introduced, forexample, with an inline eductor in the solution to produce the newcompound, which will be referred to as hydrogen glycine. In theembodiment outlined above, 9500 liters of hydrogen chloride gas isintroduced into the solution.

Although not intended as a limitation on the invention, applicantproposes that the following series of reactions creates the hydrogenglycine:

1NH₂CH₂COOH+1H₂O→1NH₃ ⁺CH₂COOH⁻+1H₂O  (1)

1NH₃ ⁺CH₂COO⁻+1HCI→1CI⁻.NH₃ ⁺CH₂COO⁻.H⁺  (2)

Although the invention is not intended to be limited to the followingexplanation, it is theorized that in (1) the amine group deprotonatesthe carboxylic acid group to yield glycine zwitterions. In reaction (2),the hydrogen cation and chloride anion interact with the glycine. It maybe that, owing to the differences in the dissociation constants of thecarboxyl group and the amine group, the glycine ion has a strongeraffinity for chloride than for hydrogen. The result is a solution with aminimal amount of free chloride ions and a pH typical of a strong acid,thus greatly reducing the corrosivity to near zero. The currentcomposition has a corrosion level of 0.04 mmpy, well below the limit of6.25 mmpy established in U.S. Federal DOT guidelines to receive a“non-corrosive” designation. Also, the glycine acts as a buffer,resisting changes to pH much more strongly than is known in traditionalacids.

The composition of the present invention thus maintains its strength andpH much longer than is typical for strong acids. Thus less of thepresent composition is required for a given use as compared withpreviously known acids, thereby further reducing environmental impact ascompared with known traditional strong acids.

It has been found that, not only does the inventive compound serve toreplace more acidic and caustic substances, but hydrogen glycine hasbeen found to “tame” strong acids interacting with substrates, thusreacting in such a manner as would a base, neutralizer, or an inhibitor.For example, when hydrogen chloride is placed on a metal such asaluminum or steel, a violent corrosive reaction takes place, thusgassing off (fuming) and corroding the metal surface. In addition, thefuming itself is corrosive. However, when hydrogen glycine is added tothe hydrochloric acid on the metal surface, the reaction issubstantially immediately tamed, and the corrosion and fuming stops.This same effect has been noted with other traditional acids such assulfuric acid, phosphoric acid, urea hydrochloride, and glycolic acid.This corrosion inhibition can be effected in a wide range ofconcentrations, from 0.05% to 35% hydrogen glycine in acid.

Exemplary embodiments of the present disclosure include a method ofmaking a synthetic acid comprising mixing glycine in water to form aglycine solution; and adding hydrogen chloride to the glycine solution.In one embodiment, the mixing comprises introducing the glycine into thewater with the use of an eductor pump. In another embodiment, the addingcomprises introducing the hydrogen chloride in gaseous form to theglycine solution. In yet another embodiment, the introducing comprisesusing an inline eductor.

The glycine may be mixed in the water in a weight ratio range of 1:1 to1:1.5 glycine to water. Further, the mixing may be performed with theuse of an inline static mixer. In one embodiment, the mixing continuesuntil the glycine is essentially fully dissolved in the water. Inanother embodiment, the hydrogen chloride gas is added in a molar rangeof 1:1 to 2:1 glycine to hydrogen chloride.

Other methods in accordance with the embodiments disclosed hereininclude a method of assisting in hydraulic fracturing of an oil or gaswell and adjusting the pH of well drilling fluids comprising adding toat least one of the well and the drilling fluid an effective amount of asolution of hydrogen glycine for adjusting the pH thereof to a desiredlevel.

Also disclosed is a method of adjusting the pH of at least one ofprocess and waste waters comprising adding to the at least one of theprocess and waste waters an effective amount of a solution of hydrogenglycine for adjusting the pH thereof to a desired level.

It is believed that the new compound has a multiplicity of benefits, notthe least of which is that the elements are environmentally friendly,non-toxic, and non-corrosive, the ingredients being designated as FDAGRAS (generally regarded as safe). As discussed above, the new compoundof the present invention can also replace or augment, and is safer touse than, traditional acids, and does not fume during use. Hydrogenglycine is also believed to be able to serve as a replacement fortraditional sanitizers and disinfectants such as quaternary ammonia andsodium hypochlorite.

1. A method for adjusting the pH of a fluid, the method comprising:mixing glycine with water to form a glycine solution; adding hydrogenchloride to the glycine solution to generate a solution; and adding aneffective amount of the solution to the fluid for adjusting the pHthereof to a desired level.
 2. The method of claim 1, wherein the fluidcomprises a fluid associated with at least one of an oil well and a gaswell.
 3. The method of claim 1, wherein the fluid comprises at least oneof an oil well and a gas well drilling fluid.
 4. The method of claim 1,wherein the fluid comprises at least one of a process and a waste water.5. The method of claim 1, wherein the mixing comprises introducing theglycine into the water with the use of an eductor pump.
 6. The method ofclaim 1, wherein the adding comprises introducing the hydrogen chloridein gaseous form to the glycine solution.
 7. The method of claim 6,wherein the introducing comprises using an inline eductor.
 8. The methodof claim 1, wherein the glycine is mixed with the water in a weightratio range of about 1:1 to about 1:1.5 glycine to water.
 9. The methodof claim 1, wherein the mixing is performed with the use of an inlinestatic mixer.
 10. The method of claim 1, wherein the mixing continuesuntil the glycine is essentially fully dissolved in the water.
 11. Themethod of claim 1, wherein the hydrogen chloride is added in a molarrange of about 1:1 to about 2:1 glycine to hydrogen chloride.